What role did the Soviet Union play in World War II?

The Soviet Union played a pivotal role in World War II, primarily as a key member of the Allied powers fighting against Nazi Germany on the Eastern Front. Despite an initial nonaggression pact with Germany in 1939, the Soviet Union was invaded by Germany in June 1941. The subsequent Eastern Front campaign, from June 1941 to May 1945, was a brutal and decisive theater of the war.123

Key Soviet contributions include:
* Turning the Tide: The Soviet victory at the Battle of Stalingrad in the winter of 1942-1943 marked a crucial turning point, halting the German advance and beginning the Soviet counteroffensive.45
* Military Might: Under Joseph Stalin's leadership, the Soviet Army engaged in massive campaigns, pushing German forces back across Eastern Europe and ultimately capturing Berlin.25
* Vast Sacrifice: The Soviet Union suffered immense human and material losses, with millions of soldiers and civilians killed, but its resilience and military efforts were critical to the defeat of Nazi Germany.67
* Post-War Influence: Following the war, Soviet military advances led to the establishment of communist regimes in Eastern Europe, significantly shaping the post-war geopolitical landscape and contributing to the onset of the Cold War.267